Neighboring Group Participation of the Indole Nucleus: An Unusual DAST-Mediated Rearrangement Reaction
作者:David J. Hallett、Ute Gerhard、Simon C. Goodacre、Laure Hitzel、Timothy J. Sparey、Steven Thomas、Michael Rowley、Richard G. Ball
DOI:10.1021/jo0004759
日期:2000.8.1
A rearrangement reaction involving the indole nucleus was investigated using stereochemical markers and low-temperature NMR experiments. Treatment of (3S, 4S)-3-hydroxy-4-(2-phenyl-1H-indol-3-yl)-piperidine-1-carboxylic acid benzyl ester (>90% ee) with diethylaminosulfur trifluoride gave stereospecifically (3S, 4S)-4-fluoro-3-(2-phenyl-1H-indol-3-yl)-piperidine-1-carboxylic acid benzyl ester (>90%
使用立体化学标记和低温NMR实验研究了涉及吲哚核的重排反应。用三氟化二乙基氨基硫处理(3S,4S)-3-羟基-4-(2-苯基-1H-吲哚-3-基)-哌啶-1-甲酸苄酯(> 90%ee),得到立体有择的(3S,具有完全区域选择性的4S)-4-氟-3-(2-苯基-1H-吲哚-3-基)-哌啶-1-甲酸苄酯(> 90%ee)。据信反应性螺环丙基-3H-吲哚中间体的初始形成负责反应的立体和区域化学结果。